Echo, also known as delay, is a guitar effect that produces discrete repetitions of the original signal after a certain period of time. These repetitions are called echoes and are heard as distinct, spaced-out repetitions of the original sound. Echo pedals typically offer controls for adjusting parameters such as delay time (the length of time between the original sound and each echo), feedback (the number of repetitions), and level (the volume of the echoes relative to the original signal).

Echo effects can range from subtle repeats that add depth and dimension to a guitar tone to more pronounced echoes that create rhythmic patterns and textures. They are commonly used in various musical genres, including rock, blues, ambient, and electronic music, to add atmosphere, depth, and complexity to guitar solos, riffs, and rhythm parts.

Echo pedals are versatile tools that allow guitarists to create a wide range of echo effects, from classic tape echo simulations to modern digital delays with advanced features like tap tempo and stereo output. Popular echo pedal models include the TC Electronic Flashback Delay, Boss DD-7 Digital Delay, and Strymon El Capistan.